Health

Damage taken is subtracted from a combatant's maximum Health score. When its current Health reaches 0, the combatant falls and is defeated. If a character reaches 0 Health, the party must retreat from the scene of battle and fails its current quest.

Poisoned condition lowers fortitude, which results in lowered health. This may cause current health to slide down to 0 or lower. If this happens, then the character collapses, instead of being defeated.